Barnsley have now won back to back games for the third time this season, and have now won four of their past six League One outings.
The Reds have won with back to back clean sheets for the first time since the opening two games of the season.
It is their first successive home wins with clean sheets since February 2016 when they defeated Doncaster 1-0 and Coventry 2-0.
Barnsley have had the same scoreline in back to back league games for the first time since January when they lost 3-1 to Aston Villa and then Fulham.
The game was goal-less at half time, only the fourth Barnsley league game to be 0-0 at half time this season.
It is the first time Barnsley have won this season when 0-0 at half time, drawing two and losing one of the other three and indeed is the first time they have won a game when NOT already been ahead at half time.
It the first time Barnsley have won a game that was goal-less at the break since New Year's Day at Sunderland (also 1-0)
The winner eventually arrived via Kieffer Moore after 87 minutes, Barnsley's latest WINNING goal since April against Sheffield United when Tom Bradshaw made it 3-2 after 88 minutes.
Moore is back on the goal trail after a five game drought, and moves up to joint fourth in the League One scorers list with eight goals.
He has now scored four goals in just two appearances against Southend, after grabbing a hattrick in his only previous game against the Shrimpers, for Rotherham in August 2017.
The Reds remain unbeaten when Moore has scored this season (W4 D1)
It was Moore's 21st League One goal in 35 appearances for Rotherham and Barnsley.
He has now scored 12 goals overall for the Reds, six have come at home and six away.
Moore's goal was a header from an Alex Mowatt corner, Mowatt’s eighth goal involvement this season (2 goals, 6 assists)
The result now extends Barnsley's unbeaten home start to eight matches, their best home start since 2003-2004 (11 games) and extended their overall current unbeaten home run to 12 matches, their best home run since 2007 (also 12)
Barnsley have opened the scoring in seven of their eight home matches in 2017-2018 and are still yet to be behind at Oakwell this season.
They also currently have the second best home record in League One having collected 18 points, only Luton (20) have collected more in front of their own supporters and they are one of three teams still unbeaten at home along with Luton and Sunderland.
Barnsley do have the best home defensive record in the division having conceded just five goals and have now won three on the bounce in the league at Oakwell for the first time since August 2016.
It's now just two defeats in the last 20 home games in League One (W13 D5)
The Reds are unbeaten in 17 matches when opening the scoring since a 3-1 defeat to Fulham in January.
This was the third Barnsley game this season where no bookings were issued (also Oxford and Wimbledon)
There were only 13 fouls in the game, comfortably the lowest in a Barnsley match this season.
Barnsley have won three of the last five meetings with Southend now however this result ends a run of successive defeats against the Shrimpers and successive Oakwell defeats.
Barnsley enjoyed 60% possession in the game, their highest in a match for 11 games (all comps) since enjoying 63% against Gillingham at the start of September. Bradford remain the only side to have had more ball possession than Barnsley this season.
1. Adam Davies
5. Ethan Pinnock
6. Liam Lindsay
12. Dimitri Cavare
23. Dani Pinillos
8. Cameron McGeehan
20. Brad Potts
27. Alex Mowatt
21. Mike Bähre
26. Mamadou Thiam
19. Kieffer Moore
7. Ryan Hedges (for Bähre 56)
25. Cauley Woodrow (for Thiam 66)
10. George Moncur (for Pinillos 83)
38. Jake Greatorex
3. Zeki Fryers
29. Victor Adeboyejo
33. Jacob Brown
1. Mark Oxley, 6. Michael Turner, 8. Timothee Dieng, 10. Simon Cox, 16. Dru Yearwood, 18. Sam Mantom, 23. Taylor Moore, 24. Jason Demetriou, 30. Harry Bunn, 32. Stephen Hendrie, 48. John White.
7. Michael Kightly (for Bunn 69)
31. Theo Robinson (for Cox 82)
28. Shawn McCoulsky (for Mantom 90)
22. Ted Smith, 2. Elvis Bwomono, 11. Stephen McLaughlin, 27. Harry Kyprianou.
Southend manager Chris Powell said:
Story of our season. We’ve had two tough away games and we came here and were in the game. We managed exactly what Barnsley threw at us and I thought we put in a real dogged, proper away performance.
To lose a goal like that from a set play, where we’d dealt with them throughout the game, you’ve got to keep going until the final whistle. It’s a real dagger to the heart this one because a point away from home really would have set us up going into the two cup games before our next home league game, but sadly it wasn’t to be.
SkyBet League One results:
Saturday 3rd November 2018:
(23rd) AFC Wimbledon 1-2 Shrewsbury Town (18th)
Waterfall 57, 89
(4th) BARNSLEY 1-0 Southend United (12th)
(13th) Blackpool 0-3 Bristol Rovers (20th)
(24th) Bradford City 0-1 Portsmouth (1st)
(8th) Charlton Athletic 2-0 Doncaster Rovers (9th)
(7th) Coventry City 1-1 Accrington Stanley (6th)
(17th) Gillingham 3-0 Fleetwood Town (11th)
(22nd) Plymouth Argyle 0-2 Sunderland (2nd)
McGeady pen 78
(16th) Rochdale 0-0 Luton Town (5th)
(19th) Scunthorpe United 3-3 Oxford United (21st)
(10th) Walsall 1-3 Burton Albion (14th)
(15th) Wycombe Wanderers 1-0 Peterborough United (3rd)
Barnsley lie in 4th place in Sky Bet League One with 31 points from 16 games.
We are 3 points inside the Play-Offs, 4 points off the Automatic Promotion Places, 7 points off First place and 16 points above the Relegation Zone.
Up to 04/11/18
Checkatrade Trophy Northern Group F: Barnsley v Everton Under 21s, Tuesday 6th November 2018. Kick-Off: 7:30pm
On The Road:
Sky Bet League One Matchday Seventeen: Accrington Stanley v Barnsley, Saturday 17th November 2018. Kick-Off: 3pm